Infinity is not numerically implemented in modern mathematics primarily because it can lead to confusion and contradictions, particularly in elementary algebra where operations involving infinity are often deemed undefined. While infinity appears in advanced mathematical concepts like limits and projective geometry, its treatment varies significantly across different mathematical contexts. The discussion highlights that low-level algebra's classification of infinity as undefined is intended to simplify learning and avoid misconceptions among students. There are valid mathematical frameworks that incorporate infinity, but they require careful definitions and contexts to avoid ambiguity. Overall, while infinity is a crucial concept in higher mathematics, its integration into basic arithmetic remains limited to prevent confusion.